There exist frequency hopping techniques for switching frequencies according to a hopping pattern in carrying out communication, the techniques being intended to implement communication in a manner resistant to noise and interference from other systems.
One such technique is described in PTL 1, the technique involving carrying out communication by switching from one frequency slot to another in accordance with a frequency hopping pattern. According to this technique, if there is interference in the frequency slot currently used as part of the frequency hopping pattern, that frequency slot is removed from the frequency hopping pattern. Also according to this technique, if there is no interference during reception using a communication idle time in a frequency slot yet to be used as part of the frequency hopping pattern, that frequency slot is added to the frequency hopping pattern.